Knife



Dec. 20, 1949 J, NELSON 2,491,575

KNIFE Filed Feb. 21, 1946 Patented Dec. 20, 1949 UNITED STATES PATENT OFFICE KNIFE John E. Nelson, Webb City, Mo.

Application February 21, 1946, Serial No. 649,236

1 Claim.

My invention relates to knives and more particularly to knives having a removable blade, which is formed by breaking a double-edged safety razor blade lengthwise into two approximately equal parts.

The object of my invention is to provide a knife in which the removable blade is securely and rigidly held.

Other objects of my invention may appear in the following specification describing my invention with reference to the accompanying drawing illustrating a preferred embodiment of my invention. It is however to be understood that my invention is not to be limited or restricted to the exact construction and combination described in the specification and shown in the drawing but that such changes and modifications can be made, which fall within the scope of the claims appended hereto.

In the drawing: I

Figure 1 is a vertical sectional view of a knife according to my invention, partly shown in elevation.

Figure 2 is a top plan view of the knife shown in Figure 1.

Figure 3 is an end view of the knife shown in Figure l, and

Figure 4 is a sectional view taken on line 4-4 in Figure 1.

Referring now to the drawing in detail the knife according to my invention has a handle ID. This handle has a circular cross section and a semi-globular rear end. It is tapering toward the front and has on its front end a cylindrical portion I I, on which a ferrule I2 is mounted and fastened in any convenient manner. The ferrule I2 has a round cross section and the main part of the ferrule is tapered forwardly just like the handle I0. The forward end I3 is shaped cylindrically and has a somewhat smaller diameter than the forward end of the tapering ferrule portion, thereby forming a shoulder I I on the ferrule. The cylindrical ferrule part I3 has a slot I5 therein, just wide enough to receive a longitudinal half of a double edged safety razor blade therein.

A cap I6 is firmly but removably mounted on the cylindrical part I3 of the ferrule I2 and the bottom I1 of the cap It has a slot I8 therein of the same width as the slot I5 in the ferrule por- 1 tion I3 and coinciding therewith when the cap It is mounted on the ferrule.

A guard I9 has a U-shaped cross section and is either permanently fastened onto the cap I6 or integrally formed therewith so that the guard extends forwardly from the bottom I! of the cap' and that the channel formed by the guard willcoincide with the slot I8 in the cap bottom.

A plunger 20 is arranged slidably in the cylindrical ferrule portion I3 and has a forwardly extending projection 2I thereon, the inner surface 22 whereof is flattened.

The plunger 20 extends rearwardly into the tapered main part of the ferrule I2 and has a centrally located and axially and rearwardly extending cylindrical lug 23 thereon. A spiral spring 24 abuts the front face of the cylindrical handle part II with one of its ends, surrounds the lug 23 and abuts the plunger 20 with its other end, urging the plunger forwardly. A threaded hole 25 extends diametrically through the plunger and is arranged vertically to the flattened surface 22 on the plunger projection 2 I.

A screw 26 engages this threaded hole 25 and a slot 21 is provided in the ferrule I2 right behind the shoulder I4 to permit the screw 26 to enter therethrough and to slide therein. The screw '26 has a knurled head 28 to facilitate the tightening and loosening of the screw.

When the knife is assembled the slot 21 is located on top and the plunger projection 2I on the bottom.

In the rear end of the handle ID a razor blade breaker 29 is provided consisting of a headless screw having a diametrical slot 30 therein. A double edged razor blade can easily be broken in two longitudinal parts by inserting its ends into the slot 30.

One such blade portion 3| is inserted in the channel of the guard I9, after the unit consisting of said guard and the cap I6 is removed from the ferrule I2, so that a broken end portion 32 of the blade will extend upwardly inside the cap I6 beyond the slot I8 and the top edge of the guard I 9. The screw 26 is loosened in the plunger 20 and the plunger is pulled back in the ferrule by means of the screw head '28. Then the screw is tightened pulling the plunger upwardly in the bore of the ferrule and preventing it from forward movement under pressure of the spring 24. The capand guard with the blade 3| therein is then mounted on the ferrule and the screw 26 is loosened. The spring forces the plunger 20 forward. The forward face of the plunger engages the end of the plate 3i pressing the upward extending blade portion 32 against the inside surface of the cap bottom II. At the same time the plunger projection 2| engages the end shoulders formed on all double-edged safety razor blades l 3 with its forward end and with the flattened surface 22. The screw 26 is tightened again securing the plunger 20 against accidental rearward movement and thereby also securing the blade 3| in working position.

Having described my invention what I claim and desire to secure by Letters Patent is:

A knife comprising a handle, a ferrule fixed on one end e i ai i ha d andha in ses e e a therein, a; cap; comprising a cylindricalgportion detachably secured onone end of said' ferrule, an end-wall secured to one end of said cylindrical portion and having a narrow, diametrical slot therein, and an elongated guard of U-shaped cross-section projecting outwardly from said end wall with the channel formed thereby 'coiricid'ing with said slot, said slot terminatingshort oi the edge of said end-wall adjacent the closed side of said guard to provide a shoulder within said cap, a plunger within said ferrule having a projectionon the en'd' therof'facing "said can end wall which projection isdisposed opposite the end REFERENCES CITED The following references are of record in the file of thispatent:

UNITED STATES PATENTS Number Name Date 1,448,730 Davis Mar. 20, 1923 484,657 Larzel'ere Feb. 26, 1924 2,234,532 Nelson Mar. 11, 1941 

